How do I fix this Wrist Twist Issue
You don't tell a lot about what's the issue and you're trying to do.

From your last picture it might be that the orientation of your bone is not aligned on the others. Display the axis visibility in the Properties panel > Object Data > Viewport Display > Axes. If that's the case, select it in Edit mode and CtrlR + value to rotate, or ShiftN to automatically align.



Also, maybe you should try this:


Make sure that your arm has enough topology.





For your armature, in the Properties panel > Object Data > Viewport Display, choose Display As > B-Bones (bendy bones) so that they you can twist them (CtrlAltS to scale in Edit mode).





Select your forearm bone and segment it.






Give it a Copy Rotation constraint, Space > Pose Space/Pose Space. You can reduce its influence if you want.